Quick Reference Guide
Important: If the pacing mode is set to VOO/AOO/DOO or the pulse generator box is left in 'emergency mode', escalate to a senior member of the medical team immediately. These modes are typically only used in theatre or temporarily in emergencies.
Basic Set-up for Epicardial Pacing
Figure: Epicardial pacing wires connected to pulse generator (pacing box)
Pulse Generator Settings Overview
Figure: Osypka Pace 203H pulse generator showing key settings
Key Settings:
- Mode: Determines which leads are paced and how the pacer responds to intrinsic cardiac activity
- Rate: Determines how often the pulse generator delivers an electrical impulse (typically 80 bpm)
- Output (V-Stim/A-Stim): Amount of energy delivered to trigger depolarisation (typically set at twice threshold)
- Sensitivity (V-sense/A-sense): Amount of current required to detect intrinsic activity (typically 1mV)
Commonly Used Pacing Modes
| Mode |
Chambers |
Description |
Indications |
VVI (Ventricular demand pacing) |
Single |
Ventricle is sensed; pacemaker only delivers impulse if no electrical activity within set interval |
• On-demand ventricular pacing
• Common in transvenous/epicardial pacing
• Overdrive pacing for ectopic suppression
|
DDD (Dual chamber demand pacing) |
Dual |
Both chambers sensed. Paces atrium and/or ventricle as needed based on intrinsic conduction |
• All indications except atrial tachyarrhythmias
• Common in epicardial pacing with both wires
• Maintains atrial kick
|
Daily Nursing Safety Checks
Complete at start of each shift:
- ✓ Check battery status on pulse generator screen
- ✓ Ensure spare battery (9V) taped to equipment cabinet
- ✓ Ensure continuous ECG monitoring with pacemaker mode ON
- ✓ Verify pacing spikes visible on ECG monitor
- ✓ Check all connections tightly secured (wires to pulse generator)
- ✓ Inspect pacing wire entry sites for signs of infection
Daily Medical Pacing Checks
| Procedure |
Frequency |
Rationale |
| Assess underlying cardiac rhythm |
Daily on consultant ward round
(Consultant must be present if patient pacing-dependent) |
Assess ongoing need for pacing and inform permanent pacemaker requirements |
| Review pacing mode, rate, and necessity |
Daily on consultant ward round |
Optimise pacing parameters to patient condition |
Check output threshold and set amplitude
(Typically 25-50% above threshold) |
Daily on consultant ward round
(Consultant must be present if patient pacing-dependent) |
Monitor for rising threshold; ensure margin of safety
If threshold >10V: consider cardiology referral for alternative pacing |
Check sensitivity settings
(Typically 1mV or 1/3 R-wave amplitude) |
Daily on consultant ward round |
Provide margin of safety to avoid under-sensing and R-on-T |
Emergency Set-up of VVI Pacing
Seek help immediately from senior medical team:
• GICU: Consultant or Airway Resident
• CICU: Consultant or Registrar
If haemodynamic compromise: PULL EMERGENCY BUZZER
Figure: Emergency VVI pacing set-up procedure
- Screw tighten the grey leads to the patient's ventricular wires
- Screw tighten the pins of the grey leads into the Ventricle (V) ports on the pacing box
- Turn ON
- Unlock
- Check the box has defaulted to the following settings (if not, select them):
- a) Ensure unlocked
- b) Select VVI mode
- c) Set the RATE dial to 80bpm
- d) Set the V-SENSE dial to 1.0mV
- e) Set the V-STIM dial to 8.0V and increase until capture
- Monitor for consistent capture at 80bpm, then seek help immediately
After emergency pacing instituted: Ensure senior medical team assessment and consider cardiology input
Loss of Paced Rhythm - Emergency Response
Seek help immediately:
• GICU: Consultant or Airway Resident
• CICU: Consultant or Registrar
If haemodynamic compromise: PULL EMERGENCY BUZZER
If unresponsive: Follow ALS while addressing pacing issues
Contact: Cardiology +/- Cardiac Surgery Registrar
Figure: Troubleshooting flowchart for loss of paced rhythm
- Set ventricular amplitude (V-Stim) to maximum output
➜ If no pacing capture, proceed to step 2
- Check all connections from patient to pacing box
➜ If no pacing capture, proceed to step 3
- Check battery indicator and replace if depleted
Note: Osypka 203H has 30-second backup during battery change
➜ If no pacing capture, proceed to step 4
- Trial switching polarity: Swap positive and negative terminals of ventricular wires at pulse generator
➜ If pacing restored: Success
➜ If no pacing capture: Proceed to step 5
- Consider transcutaneous pacing
After resolution: Reassess with senior medical and cardiology input. Ensure pulse generator box is NOT left in emergency mode after adequate rhythm restored.
Background
Epicardial and transvenous pacing are temporary methods of supporting bradycardia, bradyarrhythmias and tachyarrhythmias until resolution or definitive treatment is completed, typically by permanent pacemaker insertion.
In the initial emergency management of bradycardia, pharmacological agents are usually sufficient. However, in peri-arrest or cardiac arrest patients where this is insufficient and epicardial/transvenous pacing wires are not already in situ, non-invasive transcutaneous pacing is recommended as a temporary measure whilst more definitive temporary transvenous pacing is urgently organised.
Note on Transcutaneous Pacing:
Transcutaneous pacing is not covered in this guideline. Guidance is available from Resuscitation Council UK (Soar et al., 2021).
Indications for Temporary Cardiac Pacing
Bradyarrhythmias:
- Bradycardia causing haemodynamic instability
- Bradycardia due to electrolyte disturbance, toxicities, or surgery
- Sinus node disease due to acute myocardial infarction
- Heart blocks or asystole causing life-threatening haemodynamic instability
- Syncope at rest
- Intra- and post-operative management in cardiac surgery
Tachyarrhythmias (Overdrive Pacing):
- Suppressing ventricular tachycardia
- Managing Torsades de Pointes
Mechanism: A pacing rate faster than the tachyarrhythmia is selected. Overdrive pacing suppresses the arrhythmia, with rate decreased once suppression achieved.
Advantages: Epicardial and transvenous pacing are more reliable, durable, and better tolerated than transcutaneous pacing (Reade, 2007).
Historical Context
Temporary epicardial wires have been used since the 1960s for intra- and post-operative management of bradycardia, bradyarrhythmias, and tachyarrhythmias in cardiac surgery (Khorsandi et al., 2012).
Types of Temporary Cardiac Pacing Wires
Epicardial Temporary Pacing Wires
Figure 1: Epicardial pacing wires with insertion needle (removed after wires sutured to epicardial surface)
Description
- Material: Thin stainless-steel wires insulated with Teflon
- Insertion: Sutured to epicardial surface of right atrium or right ventricle with dissolvable sutures during cardiac surgery
- Wire types: Atrial, ventricular, or both may be inserted
- If only one set present: Always ventricular
- Wire location identification:
- Ventricular wires: Emerge on LEFT of sternum (usually white)
- Atrial wires: Emerge on RIGHT of sternum (usually blue)
- System types: Unipolar or bipolar
Unipolar vs Bipolar Systems
| System |
Description |
Advantages/Disadvantages |
| Unipolar |
• Single wire (negative anode) attaches to epicardium
• Second positive electrode (ground) required:
- Second pacing wire, OR
- Metal hypodermic needle through skin, OR
- Rarely: epicardial wire in subcutaneous tissue |
• Higher current required
• More electrical interference
• Less commonly used now |
| Bipolar |
• Single wire with two insulated conductors to epicardial surface
• Both electrodes within heart
• Heart muscle and intraventricular blood complete circuit
• Electrode spacing: 2.5-30mm |
• Less electrical current required
• Less electrical interference
• Most commonly used
• Note: Greater electrode distance = higher current needed = more inflammation |
Important: When electrodes placed too far apart, this can affect ability to sense electrical activity. Spacing >30mm increases inflammation and decreases system effectiveness duration.
Duration of Effectiveness
Epicardial wires deteriorate gradually over time:
- Reliable pacing and sensing functions normally lost over 5-10 days
- Shorter duration compared to transvenous wires
Figure 2: Complete epicardial pacing system showing wires attached to patient cable plug, patient cable, and pulse generator box
Transvenous Cardiac Pacing Wires
Transvenous temporary cardiac pacing provides life-saving emergency therapy for patients with bradycardia and arrhythmias causing haemodynamic instability. It can be used as a bridging technique when permanent pacemaker insertion is not immediately indicated or available (Tjong et al., 2019).
Insertion Procedure
Insertion Details:
- Operator: Skilled trained operator required
- Setting: Fully equipped temporary pacing room with trained team
- Access: Central venous access via Seldinger technique
- Preferred sites: Right internal jugular, left subclavian (more direct anatomical route)
- Sites to avoid: Left subclavian and left cephalic (potential permanent pacemaker sites)
- Venous sheath: Allows blood sampling and drug administration via side arm
- Bipolar single temporary transvenous catheter floated under fluoroscopic guidance through right heart whilst ECG monitored
- Wire with deflated balloon passes through:
- Right atrium
- Tricuspid annulus
- Right ventricle (tip pointing down into apex)
- Balloon inflated:
- Sits against right ventricular wall
- Protects from damage
- Keeps in place during deep inspiration
- Placement confirmed by:
- Chest X-ray
- Successful pacing attempt
Potential Complications:
- Damage or perforation to valves or ventricle
- Transient ventricular arrhythmias on insertion (normal finding)
- Pneumothorax (exclude with chest X-ray on return to ICU)
Figure 3: Transvenous pacing wire showing sheath, cordis, electrical ports, and balloon
Figure 4: Transvenous pacing wire in correct position - tip and balloon inflated within apex of right ventricle
Electrocardiographic Features
QRS Morphology in Paced Rhythms:
- Right ventricular pacing (transvenous/epicardial): LBBB-like QRS morphology
- Left ventricular pacing (epicardial): RBBB-like QRS morphology
- Atrial pacing: Pacing spikes before P wave
- Ventricular pacing: Pacing spikes before QRS complex
Figure 6: Atrial and ventricular pacing spikes in a paced rhythm
The Pulse Generator (Pacing Box)
The pulse generator (commonly called "pacing box" in clinical practice) is battery-operated and attached to epicardial or transvenous pacing wires, supplying them with electrical current. Several companies manufacture pulse generators, but basic important functions are similar across devices.
Figure 5: Osypka Pace 203H pulse generator (commonly used at Bristol Royal Infirmary)
Key Functions
The pulse generator allows adjustment of:
- Pacing mode
- Pacing rate
- Pacing output
- Sensitivity to intrinsic activity
Critical Understanding: It is crucial that operators understand these settings to provide safe temporary pacing to patients (Yartsev, 2021).
Understanding Cardiac Pacing
1. Pacing Mode
Definition:
Mode determines which leads are paced and how the pacer responds to intrinsic cardiac activity.
Mode Selection Options
Pacing modes are selected on the pulse generator by the operator. One of the following two modes is selected:
| Mode |
Description |
Use |
| Fixed |
Pacemaker paces at a fixed, constant rate |
Used for overdrive pacing when higher rate set to suppress tachyarrhythmias |
| Demand |
Pulse generator will NOT pace if intrinsic activity sensed |
Most commonly used pacing mode |
Single Chamber Modes
If pacing wires lead to only a single chamber (atrium or ventricle):
| Chamber |
Mode |
Full Name |
| Atrial |
AAI |
Atrial demand pacing |
| AOO |
Asynchronous atrial pacing |
| Ventricular |
VVI |
Ventricular demand pacing |
| VOO |
Asynchronous ventricular pacing |
Dual Chamber Pacing Modes
In dual chamber modes, pacing wires must be present in both atrial and ventricular chambers. Can use single chamber modes OR:
- DDD (Dual chamber demand pacing)
- DOO (AV sequential asynchronous pacing)
- DVI (AV sequential, ventricular inhibited)
- DDI (AV sequential, non-P-synchronous, with dual chamber sensing)
Dual Chamber Advantage:
Pacing both chambers improves cardiac output by adding atrial systolic volume to diastolic filling of ventricle, improving haemodynamic stability (Yartsev, 2018).
Mode OOO: Pulse generator turned OFF
British Pacing and Electrophysiology Group (BPEG) Code
This standard code helps interpret pacing mode settings:
| Position |
Meaning |
Options |
| 1st Letter |
Chamber(s) Paced |
O = None A = Atrium V = Ventricle D = Dual (A+V) |
| 2nd Letter |
Chamber(s) Sensed |
O = None A = Atrium V = Ventricle D = Dual (A+V) |
| 3rd Letter |
Response to Sensing |
O = None T = Triggered I = Inhibited D = Dual (T+I) |
Detailed Mode Descriptions
VVI (Ventricular Demand Pacing)
Single Chamber Mode
How it works:
- Ventricle is sensed
- If QRS produced: pacemaker will NOT deliver electrical impulse
- Pacemaker only delivers impulse if NO electrical activity within interval specified by set pacing rate
Indications:
- On-demand ventricular pacing with ventricular backup
- Common mode in transvenous and epicardial pacing
- Overdrive pacing for suppression of ectopic beats
Advantages:
- On-demand ventricular pacing - only paces when intrinsic rate insufficient
- Good for backup pacing
Limitations:
- Difficult to assess QRS morphology (LBBB-like QRS)
DDD (Dual Chamber Demand Pacing)
Dual Chamber Mode
How it works:
- In normal intrinsic atrial and ventricular conduction: no pacing response required (both chambers sensed)
- If loss of atrial-ventricular conduction: pacemaker paces ventricle at sensed atrial rate
- If loss of atrial activity: pacemaker paces atrium, then ventricles if no ventricular conduction after pre-determined delay (A-V delay)
Indications:
- All indications for pacing EXCEPT atrial tachyarrhythmias
- Commonly used in epicardial pacing where ventricular and atrial wires in situ
Advantages:
- Maintains atrial kick
- Versatile mode regardless of patient's conduction system
- Haemodynamic benefit from atria and ventricles contracting in synchrony
Limitations:
- Risk of endless loop tachycardia
2. Pacing Rate
Definition:
Rate controls the number of times per minute that the pulse generator delivers an electrical impulse, causing a pulse rate.
Relationship to Cardiac Output
Setting the pulse rate (beats per minute) on the pulse generator controls cardiac output:
- Cardiac Output = Heart Rate × Stroke Volume
- As heart rate increases beyond optimal point: stroke volume falls → cardiac output decreases
- Each patient has an optimal heart rate for cardiac output
- Increased heart rate comes at expense of increased oxygen consumption
Clinical Practice:
Optimal heart rate is rarely calculated. Pulse generator usually left at 80-90 bpm (Reade, 2007).
Back-up Rate
A back-up rate can be set (determined by operator, normally around 50 bpm, but some patients may require higher).
Purpose: For patients transitioning to reliance on intrinsic rhythm, provides safety backup:
- Patient remains in own intrinsic rate and rhythm until heart rate decreases below set backup rate (e.g., 50 bpm)
- If patient becomes haemodynamically compromised, backup rate triggered
3. Output
Definition:
Output is the current (measured in milliamperes, mA) delivered to each pacing lead, producing a brief pulse.
Mechanism
- Energy delivered in brief burst over ~0.6 milliseconds
- Pulse generator discharges capacitor into leads
- Electricity briefly stored in pacing leads
- Voltage between electrodes increases suddenly to 5V
- Voltage then decreases over short period (determined by lead impedance)
- Impedance: Opposition to alternating current given by effect of resistance and reactance in circuit
Capture
Definition:
Capture refers to effective stimulation of cardiac depolarisation by the pacemaker.
If pacemaker delivers electrical impulse and myocardium responds displaying QRS or P wave: successful capture
Capture Threshold
Definition:
Capture threshold is the minimum pacemaker output required to produce depolarisation of the paced chamber (Reade, 2007).
Importance:
- Higher output and current → more rapid wire encrustation → reduced effectiveness
- Important to keep output current as low as safely possible (Yartsev, 2020)
- Monitor for occasional missed beats → rising capture threshold → requires output increase
Finding the Capture Threshold
- Set pulse generator rate well above intrinsic rate (chamber continuously paced)
- Start reducing output until QRS no longer follows each pacing spike
- The minimum output at which there is still consistent capture = capture threshold
- Set output at twice the capture threshold (margin of safety)
- If electrodes become encrusted, will still continue to pace successfully
4. Sensitivity
Definition:
Sensitivity of pacing electrode is the minimum myocardial voltage (mV) needed to be detected as a P wave or R wave.
Key Concepts
Important Counter-Intuitive Relationship:
- Lower number = GREATER sensitivity
- Higher number = LOWER sensitivity
This commonly causes confusion - be aware!
| Chamber |
Sensitivity Range |
Typical Initial Setting |
| Atria |
0.4 - 10 mV |
2 mV when pacing initiated |
| Ventricles |
0.8 - 20 mV |
Problems with Sensitivity Settings
- Too low sensitivity (too sensitive): Inappropriate sensing of signals including R-on-T waves → inappropriate prevention of pacing
- Important limitation: If no significant underlying rhythm, NOT possible to assess electrode sensitivity
Checking Sensitivity Threshold
Safety Warning: NOT possible to safely check sensitivity threshold in patients with NO haemodynamically stable underlying rhythm
- Put pulse generator in VVI or DDD mode (intrinsic activity should inhibit pulse generator)
- Change rate to lower than patient's intrinsic rate
- Change output to minimum setting (capture not required, only pacing indicator LED)
- Observe sense indicator
- Increase mV dial (decreases sensitivity)
- Eventually sensitivity will be so low that intrinsic electrical activity no longer sensed
- Pacemaker unable to detect electrical activity
- Patient paced at set rate (flashing pacing indicator LED)
- Decrease mV dial (increases sensitivity)
- Eventually reach sensitivity value where pacemaker senses every P-wave or QRS interval
- This sensitivity value = sensitivity threshold
- Set sensitivity at half to one-third of sensitivity threshold
Setting Sensitivity Using Osypka Pace 203H
The Osypka Pace 203H pulse generator can identify amplitude of native P and R waves:
Safety First: Ensure patient supine in bed in case of haemodynamic changes. Cannot use if patient has NO haemodynamically stable underlying rhythm.
- Press "Pause" button
- Observe lower screen for P wave and R wave amplitude
- Set Atrial sensitivity to 1/3 P wave amplitude or as low as it will go, whichever is higher
- Only relevant in atrial or dual pacing mode
- Set Ventricular sensitivity to 1/3 R wave amplitude or as low as it will go, whichever is higher
- If in doubt: set sensitivity to as low as it will go and seek senior help
5. Assessing the Underlying Rhythm
Consultant/Senior Doctor Task: Ongoing requirement for temporary cardiac pacing should be reassessed by consultant or senior doctor on medical ward round.
Safety Precautions:
- Ensure patient supine in bed (case of haemodynamic changes)
- If significant haemodynamic compromise develops before underlying rhythm detected: ABANDON procedure
Procedure:
- Turn down pacing rate slowly until underlying rhythm revealed and can be assessed
- May not be possible to identify underlying rhythm if haemodynamic instability when pacing rate reduced below intrinsic rate
- 12-lead ECG may be completed if patient has stable underlying rhythm
Setting the Pulse Generator with Back-up Rate
Step-by-Step Procedure:
- Select a sensing MODE (either VVI or DDD)
- Temporarily DECREASE the RATE to be less than the intrinsic heart rate
- Adjust SENSITIVITY until the intrinsic complexes are detected
- Determine THRESHOLD by decreasing OUTPUT until capture is lost
- Set OUTPUT to twice the THRESHOLD
Figure: Flowchart for setting pulse generator with backup rate
Daily Nursing Care
Registered nurses caring for patients with epicardial or transvenous pacing wires should complete the following procedures at the required frequency.
Nursing Procedures Checklist
| Procedure |
Frequency |
Rationale |
Additional Information |
| Check battery status of pulse generator on screen. Ensure sufficient battery. |
Once at start of shift (safety checks) |
Prevent pulse generator and pacing failure (Reade, 2007) |
|
| Battery change (e.g., 9V battery in Osypka 203H) |
As required when low battery symbol displayed |
Prevent pulse generator and pacing failure |
Osypka 203H: Can be changed promptly during pacing - has 30 seconds backup when battery removed |
| Ensure spare battery (e.g., 9V for Osypka 203H) present in patient bed space, taped to top of equipment cabinet |
Once at start of shift (safety checks) |
Ensure spare battery immediately available in event of failure. Ensure easily identifiable if required urgently. |
|
| Ensure continuous ECG monitoring. Check ECG, BP, SaO₂% monitor alarm settings ON and correctly set. Ensure pacemaker mode turned ON and pacing spikes visible on ECG monitor. |
Once at start of shift (safety checks) |
Ensure pacing failure or arrhythmias promptly detected. Electrical interference can affect ability to see pacing spikes clearly. |
Pacemaker mode: Applies high-frequency filter, allowing clearer rhythm and pacing analysis (Reade, 2007) |
| Carefully check all connections tightly secured from pacing wires to pulse generator |
• Once at start of shift (safety checks)
• Each time patient moved |
Prevent accidental disconnection and pacing failure |
|
| Inspect pacing wire entry sites for signs of infection. Inform senior medical/nursing team if signs found. |
Once at start of shift (safety checks) |
Monitor for signs of infection |
|
| Ensure registered nurse in charge of safe movement of pulse generator during repositioning/mobilising. Check all pacing system connections correctly secured after repositioning. |
Each time patient repositioned or mobilised |
Prevent accidental disconnection and pacing failure |
|
| Record pacing observations under vital signs on computer information service (CIS) |
Hourly pacing observations: mode, rate, output, sensing, pacing activity |
Accurately record pacing requirements of patient |
|
Daily Medical Care
The medical team caring for patients with epicardial or transvenous pacing wires should complete the following checks at the required frequency and document in the patient record. Checks should be performed by member of medical team trained to perform pacing checks or pacing technicians.
| Procedure |
Frequency |
Rationale |
| Assess and record underlying cardiac rhythm |
Daily on consultant ward round
If patient pacing-dependent: Consultant must be present on unit when checks performed |
Assess ongoing need for temporary pacing. Record underlying rhythm to inform need for permanent pacing. |
| Review pacing mode, rate, and need for ongoing pacing |
Daily on consultant ward round |
Optimise pacing mode and rate to patient condition |
Check output threshold and set amplitude with margin of safety above threshold (typically 25-50% above threshold)
If threshold rising above 10V: Consider cardiology referral to explore alternative pacing methods |
Daily on consultant ward round
If patient pacing-dependent: Consultant must be present on unit when checks performed |
Monitor for rising output threshold. Ensure margin of safety in set pacing output to avoid loss of capture. |
Check sensitivity settings (typically 1mV)
Consider checking R wave amplitude and setting ventricular sensitivity (V-sense) to 1/3 R wave amplitude.
Not possible if no underlying rhythm: Set sensitivity to 1mV |
Daily on consultant ward round |
Provide margin of safety to avoid under-sensing and risk of R-on-T |
Emergency Procedures
This section provides detailed emergency protocols for managing pacing complications.
Emergency Set-up of VVI Pacing
Indication: Emergency VVI pacing can be instituted in severe bradycardia in patients with epicardial pacing wires in situ following cardiac surgery.
⚠️ SEEK HELP IMMEDIATELY from senior medical team:
• GICU: Consultant or Airway Resident
• CICU: Consultant or Registrar
If haemodynamic compromise: PULL EMERGENCY BUZZER
Figure: Emergency VVI pacing set-up procedure with detailed steps
Step-by-Step Emergency Procedure:
- Screw tighten the grey leads to patient's ventricular wires
- Screw tighten the pins of grey leads into Ventricle (V) ports on pacing box
- Turn ON
- Unlock
- Check box has defaulted to following settings (if not, select them):
- a) Ensure unlocked
- b) Select VVI mode
- c) Set RATE dial to 80bpm
- d) Set V-SENSE dial to 1.0mV
- e) Set V-STIM dial to 8.0V and increase until capture
- Monitor for consistent capture at 80bpm, then seek help immediately
After Emergency Pacing Instituted:
- ✓ Ensure senior medical team assessment of patient
- ✓ Consider cardiology input
Loss of Paced Rhythm
Recognition: Loss of pacing recognised by return of patient's underlying rhythm. May be associated with severe bradycardia and haemodynamic instability.
⚠️ SEEK HELP IMMEDIATELY from senior medical team:
• GICU: Consultant or Airway Resident
• CICU: Consultant or Registrar
If haemodynamic compromise: PULL EMERGENCY BUZZER
If patient unresponsive: Ensure ALS followed while pacing issues addressed
Contact: Cardiology +/- Cardiac Surgery Registrar (ensure coming to review)
Figure: Troubleshooting algorithm for loss of paced rhythm
Systematic Troubleshooting Protocol:
- STEP 1: Press emergency button on pulse generator box
➜ If pacing restored: Success - proceed to reassessment
➜ If no pacing capture: Proceed to Step 2
- STEP 2: Check all connections from patient to pacing box
- Verify all wires firmly connected
- Check patient cable plugs secure
- Inspect for any obvious disconnections
➜ If pacing restored: Success - proceed to reassessment
➜ If no pacing capture: Proceed to Step 3
- STEP 3: Check battery indicator and replace if depleted
- Check battery symbol on screen
- If low: Replace with spare 9V battery
- Osypka 203H note: 30-second backup during battery change
➜ If pacing restored: Success - proceed to reassessment
➜ If no pacing capture: Proceed to Step 4
- STEP 4: Trial switching polarity
Swap positive and negative terminals of ventricular wires at pulse generator
➜ If pacing restored: Success - proceed to reassessment
➜ If no pacing capture: Proceed to Step 5
- STEP 5: Consider transcutaneous pacing
- Apply defibrillator pads
- Initiate transcutaneous pacing
- Continue senior team involvement
⚠️ CRITICAL SAFETY REMINDER:
After pacing restored, reassess with senior medical and cardiology input to review safety of ongoing pacing.
ENSURE PULSE GENERATOR BOX IS NOT LEFT IN EMERGENCY MODE after adequate rhythm restored.
Safety Considerations
Magnetic Resonance Imaging (MRI) and Computerised Tomography (CT)
| Imaging Modality |
Safe? |
Explanation |
| MRI |
❌ UNSAFE |
Patients with epicardial/transvenous wires who are temporary pacing-dependent via pulse generator unsuitable for MRI. Temporary pulse generators contain too much ferrous material to be allowed into magnetic field (Reade, 2007). |
| CT |
✓ SAFE |
Patients with epicardial/transvenous wires who are temporary pacing-dependent via pulse generator can safely receive CT scanning. |
Pacing Wire Storage and Environmental Safety
Cardiac-Protected Electrical Environment
Epicardial and transvenous temporary pacing wires should be nursed in cardiac-protected electrical environment:
- Isolated electrical appliances
- Absence of carpeted floors
Minimum Monitoring Requirements
- Continuous ECG monitoring with pacing monitoring activated
- Monitor for:
- Temporary pacing failure
- Associated arrhythmias
- Immediate access to defibrillator with transcutaneous pacing capability essential
Wire Handling and Storage
Safe Handling Protocol:
- Handle wires with non-conductive gloves (reduces static electricity)
- When epicardial wires not in use: Store in non-conductive container
- Example: Plastic syringe barrel
Removal of Epicardial Pacing Wires
Important: When removing epicardial pacing wires, please refer to:
- Clinical Standard Operating Procedure (SOP): Removal of epicardial pacing wires post cardiac surgery
- Available on GICU SharePoint
- For further advice: Discuss with senior nurse or member of medical team
Transitioning to Permanent Pacemaker
Patients receiving temporary pacing through epicardial or transvenous wires may remain pacing-dependent, requiring insertion of permanent pacemaker. Timing of insertion determined by clinical course.
Wire Lifespan
- Epicardial wires: Often begin to fail after 4-5 days
- Transvenous wires: May be effective for longer (Reade, 2007)
Pre-insertion Requirements
Infection Control: Patients with clinical signs of infection and/or fever must be afebrile for at least 24 hours prior to permanent pacemaker insertion (European Society Cardiology, 2021).
References
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- European Society Cardiology (2021) 2021 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. European Heart Journal, 00, pp. 1-94.
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- Reade, M.C. (2007) Temporary epicardial pacing after cardiac surgery: a practical review. Part 1: General considerations in the management of epicardial pacing. Anaesthesia, 62, pp. 264-271.
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- Royal College of Physicians. (no date) Temporary cardiac pacing for CMT. Available at: https://www.rcplondon.ac.uk (Accessed: 23rd July 2023).
- Soar, J., Deakin, C. D., Nolan, J. P., Perkins, G. D., Yeung, J., Couper, K., Hall, M., Thorne, C., Price, S., Lockey, A., Wyllie, J., & Hampshire, S. (2021) Advanced Life Support. 8th edn. London: Resuscitation UK.
- Tjong, F.V.Y., De Ruijter, U.W., Beurskens, N.E.G., Knops, R.E. (2019) A comprehensive scoping review of transvenous temporary pacing therapy. Netherlands Heart Journal, 27, pp. 462-473.
- Yartsev, A. (2021) Anatomy of the temporary pacemaker circuit. Available at: https://derangedphysiology.com/cardiothoracic-intensive-care (Accessed: 13th July 2021).
- Yartsev, A. (2020) Sensitivity and output settings of the temporary pacemaker. Available at: https://derangedphysiology.com/cardiothoracic-intensive-care (Accessed: 23rd July 2021).
- Yartsev, A. (2018) Single and dual chamber pacing modes. Available at: https://derangedphysiology.com/cardiothoracic-intensive-care (Accessed: 20th July 2021).
Related Documents
- Quick Reference Guideline: The Management of Epicardial and Transvenous Pacing for Adult Patients
- Clinical Standard Operating Procedure (SOP): Removal of epicardial pacing wires post cardiac surgery
- Standard Operating Procedure (SOP): Competency Assessment for Registered Nurses in the removal of temporary pacing wires following cardiac surgery
Document Information
| Element |
Details |
| Authorising Body |
Surgery Governance Body |
| Dissemination Lead |
Geoff Ball |
| Document Type |
New Guideline |
| Dissemination Method |
Medical and nursing staff GICU and CICU via Sharepoint and Mystaff. Email, governance meeting, and teaching topic of the month on GICU. |
| Training |
Training already undertaken |
| Queries and Contact |
Nurse in Charge, General Intensive Care (A600) Extension 27238 |
| Audit Requirements |
Re-audit of completion of pacing checks following implementation of guideline |
Document Change Control
| Date |
Version |
Lead |
Type |
Description |
| 04/07/24 |
1.00 |
Geoff Ball |
Major |
New document |